Knowledge Base

Acquire a Trial Live

Aim

To carry out video tracking in a live situation. Video is not recorded.

Prerequisites

1. In the Experiment Settings, under Video Source select Live tracking.
2. Choose Acquisition > Open Acquisition. In the Acquisition Settings window, select Track next planned trial; do not select Save video.
3. Make sure at least one trial is planned. To add a new trial, in the Playback control window click the New trial button or press Ctrl+F3.
4. IMPORTANT: Make sure that video resolution, frame rate and duration do not exceed the values reported in Resolution, frame rate, and maximum trial duration.

Procedure

1. Choose Acquisition > Start Trial, or press Ctrl+F5, or click the Start trial button in the Playback control window.
2. Release the animal in the arena. As soon as data recording starts, the Video window says Acquiring.
3. The trial stops when the condition before the Stop track box is met, or when you choose Acquisition > Stop Trial, or press Ctrl+F6, or click the Stop trial button.

What Next?

• If you need to enter values of independent variables, click the Independent Variables tab in the Analysis Results and Scoring pane. Edit the values where needed.
• Remove the animal from the arena and repeat the procedure with the next trial.

Acquire a Trial Live + Save Video

Aim

To carry out video tracking in a live situation. Video is recorded for backup purposes. This is also useful when one needs to re-do tracking.

Prerequisites

1. In the Experiment Settings, under Video Source select Live tracking. Choose Acquisition > Open Acquisition. In the Acquisition Settings window, select both Track next planned trial and Save video.
2. Make sure at least one trial is planned. To add a new trial, in the Playback Control window click the New trial button or press Ctrl+F3.
3. Important: Make sure that video resolution, frame rate and duration do not exceed the values reported in Resolution, frame rate, and maximum trial duration.

Procedure

1. Choose Acquisition > Start Trial, or press Ctrl+F5, or click the Start trial button in the Playback Control window. EthoVision XT starts recording video, and waits for the condition to start tracking to be met.
2. Release the animal in the arena.
3. The trial stops when the condition before the Stop track box is met, or when you choose Acquisition > Stop Trial, or press Ctrl+F6, or click the Stop trial button. Video recording stops at the same time.

What Next?

• If you need to enter values of independent variables, click the Independent Variables tab in the Analysis Results and Scoring pane. Edit the values where needed.
• Remove the animal from the arena and proceed with the next trial.

Record Video, Then Acquire a Trial

Aim

To record video while the test is carried out. Video tracking is done at a later stage.

Important: With this method, the Trial Control rule is applied in the second stage (acquire trial), not during the first stage (save video). To stop video recording after a fixed time, do so manually (see below) or see the suggestions in Stop Video Recording After Some Time.

Prerequisites

1. In the Experiment Settings, under Video Source select Live tracking.
2. Choose Acquisition > Open Acquisition. In the Acquisition Settings window, select Save video only, track later.
3. Make sure at least one trial is planned. To add a new trial, in the Playback Control window click the New trial button or press Ctrl+F3.
4. Important: Make sure that video resolution, frame rate and duration do not exceed the values reported in Resolution, frame rate, and maximum trial duration.

Procedure

Record Video

1. Choose Acquisition > Start Trial, or press Ctrl+F5, or click the Start trial button in the Playback Control window. The Video window shows a message: Recording video.
2. To stop video recording, choose Acquisition > Stop Trial, or press Ctrl+F6, or click the Stop trial button in the Playback Control window. Remove the animal from the arena. You can now proceed with the next subject or track the data from the video just saved (see below).

Acquire the Trial From the Recorded Video

1. In the Acquisition Settings window, select Track next saved video file. The trial name shown next to Trial refers to the first saved video in your Trial List that you still have to track from.
2. Position the video at the point you require.
3. Select DDS in the Playback Control window to make sure that samples are not missed. See DDS (Detection Determines Speed) on page 586.
4. Choose Acquisition > Start Trial, or press Ctrl+F5, or click the Start trial button in the Playback Control window. The video is played forward and tracking takes place.
5. Acquisition stops automatically based on the Trial Control Settings, or when the video file has reached the end, or when you choose Acquisition > Stop Trial, or press Ctrl+F6, or click the Stop trial button.

What Next?

• If you need to enter values of independent variables, click the Independent Variables tab in the Analysis Results and Scoring pane. Edit the values where needed.
• If you wish to discard the track and re-do tracking from that video, see Redo a Trial on page 530.